Flaps on aircraft are deployable to change lift characteristics of a wing for certain phases of flight. For example, flaps may be stowed during climb, cruise, and descent phases of flight, may be deployed to a first degree during a takeoff phase of flight, and may be deployed to a second, greater degree during a landing phase of flight. The flaps are typically pivotably connected to the wing of the aircraft at or close to a first inboard location and a second outboard location. The flaps are also typically actuated for deployment at the first and second locations.
Flap designs have trended toward stronger and more rigid flaps. Such stiffer flaps present a challenge with respect to detecting abnormal operations in the actuation mechanisms for one side of the flap.